mypros+
Error code reference

GE Range Error Code F4x

Open oven sensor (over 4800 ohms).

GE codesGE range codes

Open oven sensor (over 4800 ohms).

First step from the service manual

Disconnect sensor harness from control. Measure resistance. Should be ~1080 ohms at room temperature with 2 ohms per degree change. Look for damaged harness/terminals/pins if resistance is OK.

The complete diagnostic procedure includes additional test steps, resistance specifications, wiring diagram references, and component test points.

MyPros+ Max

Get the full diagnostic procedure for F4x.

  • Step-by-step tests with expected resistance, voltage, and continuity values
  • Wiring diagram references and connector pinouts from the OEM service manual
  • Verified part numbers when replacement is required
Get the full procedure

$29/month · Cancel anytime · Or $9.95 3-day pass

What F4x means on a GE range

The F4x error code on a GE range indicates an open oven temperature sensor circuit. The control board continuously monitors the resistance of the oven sensor (also called an RTD, or resistance temperature detector) to track cavity temperature. When the measured resistance exceeds 4800 ohms, the control interprets this as an open circuit and triggers the F4x fault. Under normal conditions, the sensor should read approximately 1080 ohms at room temperature, with resistance increasing at a rate of roughly 2 ohms per degree Fahrenheit as temperature rises.

The oven sensor is a two-wire probe typically mounted through the rear wall of the oven cavity. It connects back to the control board via a wiring harness. An open circuit in this loop can originate at the sensor probe itself, along the harness, or at the connector terminals where the harness meets the control board. Because the resistance is above 4800 ohms rather than within a reasonable range, the control cannot calculate a valid temperature reading and disables heating to prevent an unsafe runaway condition.

The most reliable first diagnostic step is to disconnect the sensor harness at the control board and measure resistance directly across the sensor leads with a multimeter. A reading near 1080 ohms at room temperature confirms the sensor is functional, which redirects attention to the harness and terminal connections. A reading that is significantly higher or reads OL (open loop) on the meter points to a failed sensor probe. Burned, corroded, or pushed-back terminals at either the sensor connector or the control board connector are common culprits and should be carefully inspected even when sensor resistance checks out.

Source: manufacturer service documentation.

Common causes of F4x

  1. 01

    Failed oven temperature sensor

    Part replacement

    The sensor probe itself has developed an open circuit internally, causing resistance to read above 4800 ohms. Confirm this by measuring resistance directly at the sensor leads: a reading significantly above 1080 ohms at room temperature indicates a defective sensor that needs replacement.

  2. 02

    Damaged or broken wiring harness

    Part replacement

    The wiring between the sensor and control board can crack, burn, or break, especially near the oven cavity where heat exposure is high. Visually inspect the full length of the harness for scorched insulation, pinched sections, or visible wire breaks.

  3. 03

    Corroded or damaged connector terminals

    Wiring / connection

    Corrosion, arcing, or physical damage at the harness connector pins can interrupt the circuit even when the sensor and wiring are intact. Inspect the terminal pins at both the sensor connector and the control board connector for discoloration, pitting, or pins that have backed out of their housing.

  4. 04

    Loose or disconnected harness connector

    Wiring / connection

    A connector that has partially or fully pulled free from the control board or sensor will produce an open circuit reading. Check that both ends of the sensor harness are fully seated and latched.

  5. 05

    Faulty control board

    Part replacement

    If the sensor measures approximately 1080 ohms at room temperature and the harness and connectors show no damage, the control board's sensor input circuit may have failed. This is the least common cause and should only be considered after all other components are confirmed good.

See the test procedure for each cause

Frequently asked questions about F4x

What does F4x mean on a GE range?
The F4x code on a GE range means the control board has detected an open circuit in the oven temperature sensor loop, with a measured resistance exceeding 4800 ohms. The sensor should normally read around 1080 ohms at room temperature. The oven cannot regulate heat safely without a valid sensor signal, so the control disables the heating system and displays this fault.
Can I fix the F4x error myself?
Many technicians and experienced DIYers can resolve this fault by testing and replacing the oven sensor, which is typically accessible from inside the oven cavity with basic hand tools. Start by disconnecting the sensor harness at the control board and measuring resistance with a multimeter. If the sensor reads well above 1080 ohms or shows an open circuit, replacing the sensor is a straightforward repair. If the sensor tests correctly, the fix requires closer inspection of the wiring harness and connector terminals.
Is it safe to use my GE range while the F4x code is showing?
It is not recommended to operate the oven with an active F4x fault. The control board cannot monitor oven temperature without a functioning sensor signal, which means it cannot prevent the oven from overheating or underheating. Bake and broil functions should be considered unreliable until the sensor circuit is repaired.
How much does it cost to repair an F4x error on a GE range?
If the oven sensor itself is the cause, the part typically costs between $20 and $60 depending on the model, and the repair is often something a homeowner can do without a service call. If a professional technician is needed, expect labor costs to bring the total repair into the $100 to $250 range. Control board replacement, if required, would cost significantly more, generally $150 to $400 or higher for parts alone.
Will resetting the range clear the F4x error code?
Resetting the range by cycling the circuit breaker or unplugging it may temporarily clear the F4x code, but the fault will return as soon as the control board reads the sensor circuit again if the underlying problem has not been fixed. A reset is useful for confirming whether the fault is persistent, but it is not a repair. The sensor circuit must be properly diagnosed and the faulty component replaced to resolve the error permanently.

Related GE range codes

All GE range codes
View all 303 GE range codes

78,000+ service manuals · 160,000+ error codes · 55+ brands

Get Started

$29/month · Cancel anytime · Or $9.95 3-day pass